Mixed polymerization products



Patented May 31, 1938 UNITED STATES PATENT OFF-ICE LHXED POLYMERIZ ATION PRODUCTS No Drawing. Application January 3, 1938, Serial No. 183,119. In Germany March 5, 1932 8 Claims.

This invention relates to mixed polymerization products of a vinyl ester of an aliphatic car,- boxylic acid containing from to 6 carbon atoms and another polymerizable organic substance and to a process of producing the same.

This application is a continuation-in-part of our copending application Ser. No. 79,268, filed May 12, 1936 which in turn is a continuation-inpart of Ser. No. 658,146. filed February 23, 1933.

We have found that valuable products are obtained by subjecting to polymerization mixtures of a vinyl ester of an aliphatic carboxylic acid containing from 5 to 6 carbon atoms in the molecule and another polymerizable organic substance.

Suitable vinyl esters of the said kind are for example valeric acid, isovaleric acid, caproic acid, alpha-methyl-valeric acid. As other polymerizable organic substances adapted to be interpolymerized with said vinyl esters may be mentioned vinyl esters of lower fatty acids, such as the vinyl esters of acetic acid, chloracetic acid, propionic acid and butyric acid, vinyl halides, such as vinyl bromide and especially vinyl chloride, styrene, acrylic esters, in particular methyl and ethyl esters of acrylic acid, esters of homologues of acrylic acid, such as alpha-methyl acrylic acid, acrylic nitrile, vinyl ketones, such as vinyl ethyl or vinyl normal-butyl ketones and diolefines, as for example butadiene.

The interpolymerization of vinylesters of allphatic carboxylic acids containing from Ste 6 carbon atoms with the aforesaid substances capable of being polymerized may be effected by irradiation and/or heating. Knownpolymerization catalysts, such as oxygen in any form, as for example free oxygen, organic peroxides, as for example acetyl or benzoyl peroxides, or peracetic or perbenzoic acids, inorganic peroxides, as for example hydrogen peroxide or barium peroxide.

or other inorganic agents supplying oxygen, such as perborates or percarbonates, especially of alkali and alkaline earth metals, such as sodium, potassium, lithium, barium, calcium or strontium, silver oxide or ozone, may be addedto the esters in order to accelerate the polymerization. The said catalysts are generally added in an amount of from about 0.1 to about 5, preferably from about 0.5 to about 2 per cent by weight of the said esters, if desired together with organic acids or acidanhydrides thereof, such as acetic anhydride, which latter are usually employed in a quantity of about 10 times the weight of the catalyst used. The polymerization by heating can be carried out by boiling the polymerization gree of polymerization and also upon the amounts of the mixture to be polymerized, the desired 'degree being easily ascertained by drawing off a sample of the polymerized product from the vessel, the polymerization requiring usually at least half an hour. The reaction can also be carried out continuously, by continuously introducing monomeric compounds into the polymerization vessel at the rate at which the polymerization proceeds, the polymerized product being drawn ofi, preferably at the other end of the vessel. In this manner injurious overheating may be prevented. The said overheating may also be avoided by adding any polymerization catalyst employed in small portions only and providing sufficient time between the addition of each portion to allow the reaction mixture to cool down again to the desired temperature.

The polymerization may be carried out, if .desired, in the presence of diluents, such as water, neutral aqueous solutions, such as neutral aqueous solutions of emulsifying agents, as for example of Turkey red oil or of alkylated naphthalene sulphonic acid sodium salts, weakly acid solutions, as for example dilute aqueous acetic acid, weakly alkaline solutions, as for example 0 aqueous soap solutions, or inert gases, as for example carbon dioxide or nitrogen, if desired with the application of pressure in oneor more stages, in the presence or absence of known polymerization regulators, as for example aldehydes such as salicyl aldehyde, which may also act as solvents if a larger amount thereof be employed and/or of organic solvents, as for example ethyl alcohol, benzene, methyl, ethyl or amyl acetate, chlorbenzene, carbon tetrachloride, .chloroform, dichlorethylene, ketones, such as acetone and cyclohexanone, or nitrated hydrocarbons, such as nitrobenzene. The reaction mixture may also be polymerized in aqueous suspensions in the presence of emulsifiers and of the aforesaid polymerization catalysts. By subsequently hardening the resulting polymerization products at from to about C., products can be obtained phatic acids containing from 5 to 6 carbon atoms molecular weight have a high resistance to water.

On the other hand, the softening point of interpolymerized products obtainable from mixtures of vinyl chloride, styrene or acrylic nitrile with the said vinyl esters of aliphatic acids containing from 5 to 6 carbon atoms is considerably lowered in comparison to that of polymerization products from vinyl chloride and the like alone, whereas the elasticity and thermopla'sticity of the products is considerably improved.

If vinyl chloride, styrene or acrylic nitrile be employed in a comparatively small amount for the interpolymerization, for example if vinyl esters of carboxylic acids containing from 5 to 6 carbon atoms be interpolymerized with, say, from about 0.5 to about 20 percent by weight of one of the said polymerizable substances, the hardness and the softening points of the resulting interpolymerized products is increased with respect to that of the polymerization products resulting from vinyl esters of the said carboxylic acids alone.

The polymerization products may be employed as varnishes and lacquers, if desired together with cellulose derivatives compatible therewith, such as nitrocellulose and benzyl cellulose. The employment of mixtures of the said polymerization products with the said cellulose derivatives is very advantageous in the art 01' varnishes and lacquers because the films and coatings obtainable therefrom on surfaces of any kind, such as wood, metal, glass, paper, cardboard, leather or textile materials are very fast to light and stable to water. The polymerization products and the mixtures thereof with the aforesaid cellulose derivatives may be employed together with inert fillers, such as slate meal, carbon black or ground asbestos, with organic or inorganic pigments, such as white lead, colcothar, Indanthrene blue, Lithol Red lakes, with organic dyestuffs soluble in the organic solvents employed for the preparation of the lacquers or varnishes, and/or with softening agents such as phthalic'" esters, or neutral aryl phosphates.

The following examples will further illustrate how the invention may be carried out in practice but the invention is not restricted to these examples. The parts are by weight.

Example 1 130 parts of vinyl chloride and 30 parts of alphamethyl valeric acid vinyl ester are emulsifled in a pressure-tight vessel in 400 parts of water containing 8 parts of the sodium salt of hydroxyoctodecane sulphonic acid, 2 parts of sodium pyrophosphate and 0.5 part of potassium persulphate. The pH-value of the emulsion thus obtained ranges betweenfi and 7. The emulsion is heated at C. for about 24 hours. The polymerization is complete when the pressure decreases. The polymerization product is obtained in the form of a latex-like liquid which is coagu-, lated by the addition of dilute aluminium sulphate solution. The precipitate thus obtained is heated in the presence of a small amount of dilute caustic soda solution at about 80 C., then cooled down to room temperature, washed with water and dried. A thermoplastic product is thus obtained .which contains '76 per cent of vinyl chloride and has a softening point of about 65 C. It is soluble in halogenated hydrocarbons. It can be workedup into shaped articles in a similar manner as celluloid.

Example 2 a A mixture of 80 parts of isovaleric acid vinyl ester and 80 parts of acrylic acid methyl ester is polymerized in the manner described in Example 1 with the alternative that an open vessel is used, which is provided with a reflux condenser and that the mixture is heated to boiling. A soft tough product is obtained which is suitable for coating leather, fabrics, paper and the like.

. Example 3 It in the mixture described in Example 2'.

, methacrylic acid methyl ester be used instead of acrylic acid methyl ester, a hard product is obtained, which is soluble in the usual organic solvents and is suitable for lacquering'purposes. It yields clear colorless films.

Example 4 A mixture of 90 parts of styrene and 10 parts of alpha-methyl valeric acid vinyl ester is polymerized in the manner described in Example 2 at a temperature of between 70 and 90 C. A productis obtained which is adapted for use in injection moulding and in the preparation of insulating varnishes for electrical purposes.

As emulsifying agent there may also be used the sodium salt of oleic acid, and hydrogen peroxidetmay also be employed as a polymerizing cata- Example 5 A mixture of 250 parts of alpha-methyl valeric acid vinyl ester, 500 parts of vinyl chloride, 3000 parts of acetone and 20 parts of benzoyl peroxide is heated in a pressure-tight vessel at from 40 to C. for about 45 hours while stirring or shaking.

A viscous solution after evaporating the solvent.

Instead of acetone, methylene chloride or a mixture of acetone and benzene may be employed as solvent.

Example 6 Example 7 A mixture of 48 parts of alpha-methyl valeric acid methyl ester, 20 parts of acrylic acid ethyl ester and 12 parts of maleic acid ethyl ester is polymerized in the manner described in the foregoing example.

From the latex-like dispersion thus obtained the interpolymerization product formed can be separated by coagulation with sodium chloride. It is a soft plastic mass.

Example 8 An aqueous emulsion of 34.2 parts of alpha- The polymerization is complete when the pressure decreases. is obtained whichyields clear and colorless films methyl valeric acid vinyl ester, 45 parts of vinyl chloride and 9 parts of maleic acid isobutyl ester in 270 parts of a dilute aqueous solution of alphahydroxyoctodecane sulphonic acid sodium salt and a monomeric acrylic acid sodium salt is heated in a pressure-tight vessel at from 60 to C. for 45 hours after the addition of 0.45 part of potassium persulphate and 1 part of per cent aqueous hydrogen peroxide. A latex-like aqueous dispersion of. the interpolymerization product formed is thus obtained. It is suitable for the production of artificial leather and for coating purposes.

The dispersion may also be coagulated by an addition of a concentrated aqueous solution of sodium chloride. The solid interpolymerization product thus obtained is thermoplastic and is suitable for the production of shaped articles.

Example 9 38 parts of alpha-methyl valeric acid vinyl ester, parts of vinyl chloride and 26 parts of acrylic acid ethyl ester are emulsified in 100 parts of a dilute aqueous solution of alpha-hydroxw.

octodecane sulphonic acid sodium salt and mono sion containing about4'7 per cent of the inter polymerization product formed is thus obtained.

The dispersion is suitable for impregnating porous materials, for example paper, textiles and the like by striking it upon the surfaces of the tion products which comprises polymerizing a V mixture essentially comprising a vinyl ester. of

an aliphatic carboxylic acid containing from 5- to 6 carbon atoms and an ester of an acid of the group consisting of acrylic acid and its homologues.

2. The process of producing interpolymeriza tion products which comprises polymerizing a mixture comprising a vinyl ester of an aliphatic carboxylic acid containing from 5 to 6 carbon atoms, an ester of an acid of the group consisting of acrylic acid and its homologues and a further polymerizable vinyl compound other than vinyl chloride.

3. The process of producing interpolymerization products which comprises polymerizing a mixture essentially comprising isovaleric acid vinyl ester and acrylic acid methyl ester.

4. The process of producing interpoiymerization products which comprises polymerizing a mixture essentially comprising alpha-methyl valeric'acid vinyl ester, acrylic acid methyl ester and vinyl isobutyl ether.

5. Interpolymerization products of a vinyl ester of an aliphatic carboxylic acid containing from 5 to 6 carbon atoms and an ester of an acid of the group consisting of acrylic acid and its homoiogues.

6. Interpolymerization products of a vinyl ester of an aliphatic carboxylic acid containing from 5 to 6 carbon atoms, an ester of-an acid of the group consisting of acrylic acid and'its homologues and a. further polymerizable vinyl compound other than vinyl chloride.

7. The interpoiymerizationproduct of isovaleric acid vinyl ester and acrylic acid methyl ester.

8. The interpolymerization product of alpha-- methyl valeric acid vinyl ester. acrylic acid meth-' yl ester and vinyl isobutyl ether.

WALTER REPPE. WERNER STARCK.

ARTHUR VOSS. 

